1. Field of the Invention
The present invention relates to an auto-strobe apparatus and an auto-strobe method for the digital camera and, more particularly, to an auto-strobe apparatus and an auto-strobe method capable of automatically adjusting the flashing brightness based on different gain settings.
2. Description of Related Art
In the conventional built-in flashing technique, a simple implementation is to make the strobe apparatus complete flash or not (i.e., full or null). Also, for avoiding an excessive amount of light from radiating from a flash lamp 11, as shown in FIG. 1, an additional photo detector 12 and a comparator 13 are provided in a strobe apparatus. Hence, the brightness sensed by the photo detector 12 is compared with a predetermined reference voltage signal Vref by the comparator 13, and the flash lamp 11 is disabled when the photo detector 12 senses an appropriate amount of brightness. This can obtain a maximum flashing effect of the strobe apparatus.
For precisely controlling the flash lamp 11, data about aperture, distance from an object to be captured by the camera, etc. is also taken into consideration for calculating an more accurate predetermined reference voltage signal Vref.
However, it is known that the gain setting is critical to the brightness and quality of image captured by a digital camera. The physical meaning of the gain setting is to amplify or reduce the amount of signal from an image sensor. When the photo detector of the strobe apparatus senses an appropriate amount of light and stops flashing the flash lamp, theoretically, the image sensor is well exposed. However, because the physical meaning of the gain setting is to amplify or reduce the amount of signal from an image sensor, this image signal is amplified by the gain device, and thus the actually captured image is over-light. Thus, it is desired for the above conventional strobe apparatus to be improved to mitigate and/or obviate the problems.